Again with the corals

I know I'm probably beginning to sound a like a broken record (does anyone remember what that sounds like?), but I'd like to draw your attention once again to the plight of the planet's coral reefs. Today we have the Honolulu Declaration, in which a dozen leading reef researchers make a plea for stabilization of greenhouse-gas emissions. Will it do any good?

Probably not. While a few hundred thousand scuba diving enthusiasts, myself included (although I don't get down much, living as I do in the mountains of western North Carolina), and ecologists who understand corals' significance as marine nurseries, will mourn the pending extinctions, most folks need a far more immediate threat to get their attention.

But it's still important that biologists who understand just how serious the threat is make some noise, and I'm doing my little bit to spread the news, which is coming out of a meeting of the U.S. Coral Reef Task Force underway in Kona, Hawai'i. Specifically, the threat is acidification:

If current carbon dioxide emission trends continue, the ocean will continue to undergo acidification, to an extent and at rates that have not occurred for tens of millions of years. A doubling of the concentration of atmospheric carbon dioxide, which could occur in as little as 50 years, could cause major changes in the marine environment, specifically impacting calcium carbonate organisms. Such changes compromise the long-term viability of coral reef ecosystems and the associated benefits that they provide.

...

The most logical and critical action to address the impacts of ocean acidification on coral reefs is to stabilize atmospheric carbon dioxide (CO2) concentration. The currently high rates of coral bleaching indicate that at the present concentration (385 ppm), we have already passed temperature thresholds of most reef corals.

Aside from the collapse of the marine food web, loss of the reefs will make the Earth a less wondrous place. It's a race between the genes controlling my son's growth hormones and falling pH levels in the ocean. The winner decides whether I'll be able to take the little guy diving one day on the Great Barrier Reef.

And no, it won't be enough just to make sure some representatives reefs are afforded some degree of protection against industrial development and overfishing, as our outgoing president is threatening to do. A paper out today in PLoSOne reminds us of the limitations of that still-worthy tactic:

Existing no-take marine protected areas still support high biomass of fish, however they had no positive affect on the ecosystem response to large-scale disturbance. This suggests a need for future conservation and management efforts to identify and protect regional refugia, which should be integrated into existing management frameworks and combined with policies to improve system-wide resilience to climate variation and change.

That's from "Climate Warming, Marine Protected Areas and the Ocean-Scale Integrity of Coral Reef Ecosystems" (doi:10.1371/journal.pone.0003039) by 16 scientists from all over the place.